Leading trainer Aidan O'Brien has withdrawn Magic Wand from the Cox Plate due to lameness in the off fore leg.

The news is better for stablemate Armory, who was cleared to take his place in the field by Racing Victoria's panel of vets.

Both horses were due to be reinspected by three vets on Friday after they showed varying degrees of lameness on Thursday.

The decision paves the way for the Lloyd Williams-owned Buckhurst, who was sensationally dumped from the field and named first emergency, to run. He is a $41 chance with Sportsbet in the Cox Plate.

Racing.com